In general, an analog timepiece includes a watch case, a movement disposed in the watch case having a stepping motor which drives gear trains to operate time indicating hands, a dial, a device for illuminating the dial, a rotatable stem slidably disposed in the movement, a crown actuator disposed on the stem external to the watch case for manually rotating and sliding the stem, and a setting pinion disposed on the stem and adapted to engage the gear train when the stem is pulled from a normal "run" position to a "set" position. The crown actuator, the stem and the setting pinion may comprise what is termed a "crown setting mechanism." When in the "set" position, the crown setting mechanism is manually operated so that the setting pinion on the stem engages teeth of a setting gear which meshes with the gear train. In this way the time indicating hands may be rotated by rotating the crown actuator to set the time. An example of such an arrangement is seen in U.S. Pat. No. 5,083,300 issued Jan. 21, 1992 to Schwartz and assigned to the assignee of the present invention.
As is also known in the art, the crown setting mechanism may cooperate with the device for illuminating the dial such that when the stem is pushed from the normal "run" position to a "switching" position, the dial is illuminated. A commonly assigned, U.S. Pat. No. 5,644,553 issued Jul. 1, 1997 to Cuinet describes an example of such a combined crown and pusher. The disclosures of commonly assigned, U.S. Pat. Nos. 5,083,300 and 5,644,553 are incorporated by reference herein in their entireties.
On the other hand, a digital timepiece includes a display, a lamp for illuminating the display, manually actuatable switches (referred to hereinafter as pushers), and an integrated circuit. As is well known, the digital timepiece may have multiple operating modes such as, for example, a time-of-day (TOD) mode, a chronograph (CHRONO) mode, an alarm setting (ALARM) mode, an elapsed timer (TIMER) mode, and an alternate time zone (T2) mode. Generally, one of a plurality of the pushers is activated to change from one operating mode to another. Another one or more of the plurality of the pushers may be activated to change information being displayed during a currently activated operating mode. By example, in the ALARM mode a first pusher is actuated to select a numeric position on the display. A second pusher is actuated to sequence the numeric position through a predetermined series of numbers (e.g., 0-9) which appear on the display. To select a number within the series to represent a current value of the numeric position on the display, the second pusher is released. The first pusher is actuated again to deselect the currently selected numeric position and to select a next numeric position on the display. In this way a particular time-of-day can be specified at which time an audible alarm is activated. Examples of such multi-mode, multi-functioning electronic timepieces include commonly assigned, U.S. Pat. No. 4,783,773 issued Nov. 8, 1988 to Houlihan et al., U.S. Pat. No. 4,780,864 issued Oct. 25, 1988 to Houlihan and U.S. Pat. No. 4,283,784 issued Aug. 11, 1981 to Horan. The disclosure of these commonly assigned, U.S. Pat. Nos. 4,783,773, 4,780,864, and 4,283,784 are incorporated by reference herein in their entireties.
As the number of available operating modes and information to be displayed and set during each operating mode increases, there is likewise an increase in the number of pushers needed to activate the modes and/or set the information displayed therein. While the increasing number of modes increase the complexity of use, the increase in the number of pushers may lessen the aesthetic appeal of the timepiece. For example, the complexity in use may increase due to the need to identify which one of the pushers should be actuated to cycle through the various operating modes and/or information displayed in one of the operating modes. The increased complexity can be frustrating to a user of the timepiece.
The inventor of the present invention has realized that the setting functions performed with the crown setting mechanism of the analog timepiece are more intuitive for users than the setting functions performed with the plurality of pushers of conventional digital timepieces.
Commonly assigned, U.S. Pat. No. 3,874,162 issued Apr. 1, 1975 to Boxberger et al. ('162 patent) and U.S. Pat. No. 4,031,341 issued Jun. 21, 1977 to Wuthrich et al. describe dual function pushers and rotating switch assemblies for activating features of digital, electronic watches. For example, the '162 patent describes a stem detent and switch assembly which may provide a four position rotary detent action to advance or reset hour, minute and second counters, to select an operating mode, or to shut down the digital watch.
In commonly assigned U.S. Pat. No. 4,209,976 issued Jul. 1, 1980 to Flumm ('976 patent), a rotatable switch mechanism having a single gear-toothed wheel mounted on a rotatable and axially moveable stem, a switch assembly and circuitry for actuating time correction, is described. The switch assembly includes a first and a second switch contact and a central switch blade disposed therebetween. The central switch blade is precisely positioned within a periphery of the teeth of the single gear-toothed wheel. As the stem is rotated, the teeth of the single gear-toothed wheel deflect the central switch blade to strike either of the first or the second switch contacts. The time correction circuitry detects the striking of the switch blade and one of the switch contacts and, in response thereto, increments or decrements a displayed time based on a respective contact. For example, the striking of the first contact as a result of a clockwise rotation of the stem increments the displayed time, whereas the striking of the second contact as a result of a counterclockwise rotation of the stem decrements the displayed time.
A perceived disadvantage in the '976 patent is the precise alignment required between the single gear-toothed wheel, the central switch blade, the first contact and the second contact to activate the time correction circuitry. That is, a misalignment in the described configuration of these components due, for example, to varying manufacturing tolerances, would result in a failure of the switch mechanism of the '976 patent.
In contrast to the prior art, the present invention provides a crown switching mechanism which utilizes a minimum of associated parts, a plurality of axial setting positions and a configuration of components to improve the manual control of and operations associated with time correction. The present invention further minimizes the effects of manufacturing tolerances in components used to activate time correction circuitry.
Therefore, a crown switching mechanism that overcomes the aforementioned differences and achieves the following advantages is desired and is provided by the present invention.